U.S. patent application number 13/048136 was filed with the patent office on 2012-09-20 for method and apparatus for a flat top light source.
This patent application is currently assigned to AVAGO TECHNOLOGIES ECBU IP (SINGAPORE) PTE. LTD.. Invention is credited to Meng Ee Lee, Eng Chuan Ong, Chin Ewe Phang.
Application Number | 20120235188 13/048136 |
Document ID | / |
Family ID | 46827781 |
Filed Date | 2012-09-20 |
United States Patent
Application |
20120235188 |
Kind Code |
A1 |
Phang; Chin Ewe ; et
al. |
September 20, 2012 |
Method and Apparatus for a Flat Top Light Source
Abstract
A light-emitting device and method for manufacturing the device
are disclosed. In one embodiment, the light-emitting device
comprises a flat substrate and an encapsulation layer formed above
the flat substrate. The top portion of the encapsulation layer is
flat and the encapsulation layer is divided into a high density
layer and a low density layer. The high density layer is formed
from a wavelength-converting material precipitated on one side of
the encapsulation layer. In the low density layer, the
wavelength-converting material exists in particle form suspended
within the encapsulation layer.
Inventors: |
Phang; Chin Ewe; (Penang,
MY) ; Lee; Meng Ee; (Penang, MY) ; Ong; Eng
Chuan; (Penang, MY) |
Assignee: |
AVAGO TECHNOLOGIES ECBU IP
(SINGAPORE) PTE. LTD.
SINGAPORE
SG
|
Family ID: |
46827781 |
Appl. No.: |
13/048136 |
Filed: |
March 15, 2011 |
Current U.S.
Class: |
257/98 ;
257/E33.061 |
Current CPC
Class: |
H01L 2224/8592 20130101;
H01L 33/508 20130101; H01L 2924/00014 20130101; H01L 2924/00012
20130101; H01L 2924/181 20130101; H01L 2924/181 20130101; H01L
2224/48091 20130101; H01L 2933/0041 20130101; H01L 2224/48091
20130101 |
Class at
Publication: |
257/98 ;
257/E33.061 |
International
Class: |
H01L 33/50 20100101
H01L033/50 |
Claims
1. A light-emitting device, comprising: a substrate, the substrate
having top and bottom surfaces; a light source die attached to the
top surface; an encapsulation layer encapsulating the light source
die and the top surface; and a wavelength-converting material
formed within the encapsulation layer; wherein the encapsulation
layer further comprises: a low density layer substantially planarly
parallel to the top surface of the substrate, wherein the low
density layer having the wavelength-converting material suspending
within the low density layer in particles form; and a high density
layer substantially planarly parallel to the top surface of the
substrate, wherein the high density layer is formed by the
wavelength-converting material precipitated on one side of the
encapsulation layer.
2. The light-emitting device of claim 1, wherein the substrate and
the encapsulation layer further comprise side surfaces that have
substantially the same perimeter with side walls that are
substantially above and below each other.
3. The light-emitting device of claim 1, wherein the high density
layer is in direct contact with the top surface of the
substrate.
4. The light-emitting device of claim 1, further comprising a wire
bond encapsulated within the encapsulation layer.
5. The light-emitting device of claim 4, wherein the wire bond is
encapsulated within the high density layer.
6. The light-emitting device of claim 4, wherein a portion of the
wire bond is encapsulated within the low density layer and another
portion of the wire bond is encapsulated within the high density
layer.
7. The light-emitting device of claim 1, wherein the encapsulation
layer further comprises a top flat surface.
8. The light-emitting device of claim 1, wherein the light source
die is a flip chip die.
9. The light-emitting device of claim 1, wherein the light-emitting
device defines a rectangular shape
10. The light-emitting device of claim 1, wherein the bottom
surface of the substrate comprises a connector pad extending from
at least one side of the bottom surface.
11. The light-emitting device of claim 1, wherein the
light-emitting device forms a portion of a camera device.
12. A method for making a plurality of light-emitting devices, the
method comprising: attaching a plurality of light source dies on a
substrate; aligning a casting member having at least one cavity to
the substrate such that the plurality of light source dies are
enclosed within the at least one cavity; fixing the position of the
casting member relative to the substrate using a casting jig;
premixing an encapsulant in liquid form having a
wavelength-converting material; dispensing the encapsulant into the
at least one cavity; allowing the wavelength-converting material to
precipitate and form thereon a high density layer, and a low
density layer, wherein the high density layer comprises
precipitated wavelength-converting material and the low density
layer comprises the wavelength-converting material suspending
within the encapsulant in particle form; curing the encapsulant
layer into solid form; removing the casting member and the casting
jig; and isolating each individual light-emitting device.
13. The method of claim 12, wherein the steps of allowing the
wavelength-converting material to precipitate and curing the
encapsulant layer are done simultaneously.
14. The method of claim 12, further comprising removing any
curvature portion of the encapsulant layer to obtain a
substantially flat encapsulant layer.
15. The method of claim 12, wherein the method further comprises
rotating the casting jig during the step of allowing the
wavelength-converting material to precipitate.
16. The method of claim 12, wherein the step of isolating each
individual light source device comprises sawing the substrate.
17. The method of claim 12, wherein the casting member comprises a
plurality of cavities and the light source dies in each cavity are
cast simultaneously.
18. The method of claim 12, further comprising wire-bonding the
light source dies to the substrate.
19. The method of claim 18, wherein the high density layer
encapsulates a portion of wire bond foamed during the wire-bonding
process.
20. A flash used in mobile devices, comprising: a flat substrate,
the substrate having top and bottom surfaces; a light source die
attached on the top surface; an encapsulation layer encapsulating
the light source die and the top surface, wherein the encapsulation
layer further comprises: a layer of low density
wavelength-converting material, the wavelength-converting material
being in particle form suspended within the encapsulation layer;
and a layer of high density precipitated wavelength-converting
material substantially planarly parallel to the top surface.
Description
BACKGROUND
[0001] Light-emitting diodes (referred to hereinafter as LEDs)
represent one of the most popular light-emitting devices today. Due
to the small form factor and low power consumption, LEDs are widely
used in electronic mobile devices as indicator lights, light
sources for Liquid Crystal Displays or LCDs, as well as flashes in
camera phones, digital cameras and video recording to devices.
Compared to Xenon flashes used in most cameras, LEDs are superior
in terms of size and power consumption. For example, an LED in a
flash application may have a thickness of 0.6 mm compared to Xenon
flashes that has a thickness of 1.3 mm. The small form factor makes
LEDs suitable in mobile camera devices or mobile phones with a
camera feature that may have an overall thickness less than 5 mm.
In addition, unlike Xenon flashes, LEDs do not require charging
time before use.
[0002] Generally, most light-emitting devices are not made for a
single application, but for multiple applications. The
light-emitting devices used in flashes are usually high power and
high output light sources. Therefore, other suitable applications
for light-emitting devices used in flashes are high power
applications, such as indicator lights, light sources used in
lighting fixtures or light sources used in infotainment displays.
Electronic infotainment display systems are usually large-scale
display systems, which may be found in stadiums, discotheques,
electronic traffic sign displays and infotainment billboards along
streets and roadways. Electronic infotainment displays may be
configured to display text, graphics, images or videos containing
information or entertainment contents.
[0003] Most of the flashes used today are white light sources.
However, light produced by light source dies in most LEDs are
generally a narrow banded light having a peak wavelength ranging
from ultra violet to green wavelength. The output of the light
source die is then typically converted to a broad spectrum white
light by means of a wavelength-converting material. One example of
a wavelength-converting material is phosphor. The
wavelength-converting material may absorb a portion of light,
resulting in light loss. The light lost is usually not substantial,
but may be significant if the wavelength-converting material is
thick.
[0004] There are several design considerations in designing a
light-emitting device, such as viewing angle, color point, heat
dissipation, power consumption and form factor, to name a few.
Generally light-emitting devices are designed giving priority to
design considerations in a primary application. For example, the
light-emitting devices targeted for a flash application in camera
devices tend to be small in form factor and have a high light
output. However, light-emitting devices can often be used outside
the targeted, primary application.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] Illustrative embodiments by way of examples, not by way of
limitation, are illustrated in the drawings. Throughout the
description and drawings, similar reference numbers may be used to
identify similar elements.
[0006] FIG. 1 illustrates a cross-sectional view of a
light-emitting device having sidewalls;
[0007] FIG. 2 illustrates a cross-sectional view of a
light-emitting device without sidewalls manufactured using a
transfer mold process;
[0008] FIG. 3 illustrates a cross-sectional view of a
light-emitting device having a layer of wavelength-converting
material coated on the light source die;
[0009] FIG. 4A illustrates a perspective view of a light-emitting
device manufactured using a group casting method;
[0010] FIG. 4B illustrates a cross-sectional view of the
light-emitting device shown in FIG. 4A taken along line 4-4;
[0011] FIG. 4C illustrates density of the wavelength-converting
material in the encapsulation layer of the light-emitting device
shown in FIGS. 4A and 4B;
[0012] FIG. 5A illustrates a perspective view of a light-emitting
device having a flip chip die manufactured using a group casting
method;
[0013] FIG. 5B illustrates a cross-sectional view of the
light-emitting device shown in FIG. 5A taken along line 5-5;
[0014] FIG. 6 illustrates a cross-sectional view of a
light-emitting device having connector pads located away from the
side;
[0015] FIGS. 7A-7H illustrate how light-emitting devices are
fabricated using a group casting method; and
[0016] FIG. 8 illustrates a flow chart representing a method for
manufacturing a light-emitting device.
DETAILED DESCRIPTION
[0017] FIG. 1 illustrates a cross-sectional view of a
light-emitting device 100. The light-emitting device 100 comprises
a substrate 110, connector pads 112, a body 120, a light source die
130, a wire bond 132 bonding the die 130 to the substrate 110, and
an encapsulant 140. The encapsulant 140 encapsulates the light
source die 130 and the wire bond 132. The body 120 defines side
walls configured to direct light from the light-emitting device.
Due to the intermolecular forces that holds the liquid together
when the encapsulant 140 is in a liquid form during the
manufacturing process, the top surface of the encapsulant 140 may
not be completely flat. The body 120 may be molded. While the body
120 may increase the reliability performance, the body 120 occupies
substantial space that may be otherwise reduced.
[0018] FIG. 2 illustrates a light-emitting device 200 without
sidewalls manufactured by means of a transfer mold process. The
light-emitting device 200 comprises a substrate 210, connector pads
212, a light source die 230, a wire bond 232 bonding the die 230 to
the substrate 210, and an encapsulation layer 240. The
encapsulation layer 240 may be formed from a B-stage encapsulant
mixed with a wavelength-converting material (not shown). A B-stage
encapsulant is an intermediate stage in the reaction of certain
thermosetting resins, in which the material softens when heated,
and swells when in contact with certain liquids, but the material
may not entirely fuse or dissolve. The wavelength-converting
material (not shown) is distributed substantially evenly in the
encapsulation layer 240. The wavelength-converting-material (not
shown) may cause light loss as a portion of light may be absorbed.
The encapsulation layer 240 may be required to have a certain
thickness, in order to enable the functionality of the
encapsulation layer 240 to protect the light source die 230 from
moisture and vibration. However, the light loss may become
significant, as the thickness of encapsulation layer 240 is
increased.
[0019] An effective way to reduce light loss is by using a thin
layer of light-converting material 350, as shown in FIG. 3, which
illustrates a cross-sectional view of a light-emitting device 300
comprising a substrate 310, connector pads 312, a light source die
330, a thin layer of wavelength-converting material 350 coated on
the light source die 330, and an encapsulation layer 340. The
encapsulation layer 340 encapsulates the light source die 330 and
the thin layer of wavelength-converting material 350. The
wavelength-converting material 350 may be attached to an upper
relatively flat surface of the light source die 330. Therefore, the
light source die 330 is usually a flip chip die. The encapsulation
layer 340 may be formed using a spin molding or a spinning process.
The encapsulation layer 340 may not be flat. In addition, the spin
molding process may not be cost effective.
[0020] One cost effective method for manufacturing a miniature
light-emitting device with minimum light loss and a flat top
surface is to use a group casting method. FIG. 4A illustrates a
perspective view of light-emitting device 400. FIG. 4B shows a
cross-sectional view of the light-emitting device 400 along line
4-4, shown in FIG. 4A. Referring to FIGS. 4A and 4B, the
light-emitting device 400 comprises a substrate 410, connector pads
412, a light source die 430, a wire bond 432 connecting the die 430
to the substrate 410, an encapsulation layer 440 encapsulating the
light source die 430 and the wire bond 432, and a
wavelength-converting material 450.
[0021] The substrate 410 is substantially flat with an upper
surface 410a and a bottom surface 410b. The substrate 410 may be a
printed circuit board (referred herein after as PCB). The bottom
surface 410b may further comprise connector pads 412. The connector
pads 412 may extend from one side of the substrate 410, as shown in
FIG. 4B. The connector pads 412 may be connected to an external
power source (not shown) for providing power to the light-emitting
device 400. The connector pad 412 may be connected to a die attach
pad (not shown) through one or a plurality of conducting
material(s), typically referred to as a "via" (not shown),
extending from the bottom surface 410b to the top surface 410a of
the substrate. The "vias", connector pads 412 and die attach pads
may function as heat dissipation vehicles, dissipating heat
generated by the light source die 430 to the surroundings.
[0022] The light source die 430 is configurable to emit light. For
example, the light source die 430 may be a semiconductor based LED
die, such as a Gallium Nitride (GaN) die, Indium. Gallium Nitride
(InGaN), or any other similar die configurable to produce light
having a peak wavelength ranging between 300 nm and 520 nm. The
light emitted by the light source die 430 is then converted into
broad-spectrum white light by the wavelength-converting material
450. The wavelength-converting material 450 may be yellow phosphor,
red phosphor, green phosphor, orange phosphor or any other material
capable of converting a narrow banded peak-wavelength light into
broad spectrum white light.
[0023] Due to manufacturing methods, the encapsulation layer 440
may further comprise a low density layer 440a and a high density
layer 440b, which is further illustrated in FIG. 4C. The
encapsulation layer 440 may formed by mixing wavelength-converting
material 450 into an encapsulant 455 in liquid form during the
manufacturing process, and subsequently the mixture is allow to
precipitate. The precipitation process may occur simultaneously
during the curing process when the liquid encapsulant is cured into
solid form. The encapsulant 455 may be epoxy, silicon or any other
similar material. The high density layer 440b is formed by a layer
of precipitated wavelength-converting material 450, as shown in
FIG. 4C. The low density layer 440a, on the other hand, is not
completely void of wavelength-converting material 450, but having
very low density of the wavelength-converting material 450
suspended within the encapsulant 455 in particle form. The details
of the manufacturing process are further discussed with reference
to FIGS. 7A-7H and FIG. 8.
[0024] Unlike the light-emitting device 200, shown in FIG. 2, the
encapsulant 455 used during the mixing process is in A-stage.
A-stage is an early stage in the reaction of certain thermosetting
resins in which the material is fusible and still soluble in
certain liquids. As the encapsulant 455 is in A-stage, the
wavelength-converting material 450 can be precipitated on one side.
This process defines the encapsulation layer 440 into the low
density layer 440a and the high density layer 440b. As the
wavelength-converting material 450 is a thin layer, light loss due
to the wavelength-converting material 450 is minimal. In the
embodiment shown in FIG. 4B, the high density layer is in direct
contact with the top surface 410a of the substrate 410. However, in
other embodiments, the arrangement may be reversed such that the
low density layer 440a is in direct contact with the top surface
410a of the substrate 410. The arrangement of low density layer
440a and the high density layer 440b depends on the orientation of
the substrate 410 during manufacturing process as discussed further
with reference to FIG. 8.
[0025] As shown in the embodiment in FIG. 4B, the wire bonds 432
are encapsulated in the encapsulation layer 440. However, a portion
of the wire bond 432 is encapsulated within the high density layer
440b, while the remaining portion of the wire bond 432 is
encapsulated within the low density layer 440a. In yet another
embodiment, the entire wire bond 432 may be enclosed within only
one of either the high density layer 440b or the low density layer
440a.
[0026] As shown in FIG. 4A, the light-emitting device 400 defines a
rectangular shape. The substrate 410 and the encapsulation layer
440 are both rectangular shapes overlapping each other completely.
In the embodiment shown in FIG. 4A, each of the substrate 410 and
the encapsulation layer 440 have four sides respectively, which are
aligned to each other, respectively. In yet another embodiment that
the light-emitting device 400 may define a flat disc shape, with
each of the substrate 410 and the encapsulation layer 440 having
similar discs that are aligned with each other.
[0027] The top surface 440c of the encapsulation layer 440 defines
a substantially flat surface without any meniscus. A meniscus is a
curve in the upper surface of a standing liquid, produced in
response to the surface of the container of the liquid such as the
mold used to form the encapsulation layer 440. A meniscus can be
either convex or concave. Due to the group casting method,
discussed more fully with reference to FIG. 8 below, meniscus can
be eliminated by means of a dummy area 745, as shown in FIG. 7H and
discussed with reference to FIG. 8 below. This is one of the
advantages of the light-emitting device 400 compared to the
light-emitting device 300 shown in FIG. 3 in which the encapsulant
340 is formed individually.
[0028] Generally, both the low density layer 440a and the high
density layer 440b may be substantially flat and planarly parallel
to the substrate 410. However, in the embodiment shown in FIGS.
4A-48, the high density layer 440b may not be completely flat. A
portion of the high density layer 440b may be enclosing and thus
defining the shape of the light source die 430. In one embodiment,
the substrate 410 has a thickness of approximately 0.1 mm, the high
density layer 440b has a thickness of approximately 0.25 mm and the
low density layer is approximately 0.35 mm. The light source die
430 has a thickness of approximately 0.15 mm. The overall thickness
of the light-emitting device 400 is approximately 0.6 mm. The
dimension of the light-emitting device 400 is approximately 2.0
mm.times.2.0 mm.times.0.6 mm. Comparing the light-emitting device
400 and the light-emitting device 100 shown in FIG. 1, the
light-emitting device 400 without the sidewalls 200 (See FIG. 1)
can be made relatively smaller. In addition, the form factor and
small size of the light-emitting device 400 is suitable for many
applications, for example, flash light in mobile devices such as
camera phones, compact cameras and any other camera devices, among
other things.
[0029] FIG. 5A illustrates a perspective view of a light-emitting
device 500 having a flip chip die manufactured using a group
casting method. FIG. 5B illustrates a cross-sectional view of the
light-emitting device 500, shown in FIG. 5A taken along line 5-5.
The light-emitting device 500 is substantially similar to the
light-emitting device 400, but differs at least in the fact that
the light-emitting device 500 does not have any wire bonds 432 as
in FIG. 4A. The light-emitting device 500 comprises a substrate
510, connector pads 512, a light source die 530, an encapsulation
layer 540 encapsulating the light source die 530, and
wavelength-converting material 550. Without the wire bond 432 (in
FIG. 4A), the light source die 530 is connected to the substrate
510 through solder balls (not shown), which may be used in flip
chip die manufacturing. The encapsulation layer 540 of the
light-emitting device 500 further comprises a high density layer
540b and a low density layer 540a, as discussed above in FIGS.
4A-4C.
[0030] FIG. 6 illustrates a light-emitting device 600, which
comprises a substrate 610, connector pads 612, a light source die
630, a wire bond 632 connecting the die 630 to the substrate 610,
an encapsulation layer 640 encapsulating the light source die 630
and the wire bond 632, and a wavelength-converting material 650.
The encapsulation layer 640 further comprises a high density layer
640b and a low density layer 640a. The light-emitting device 600 is
substantially similar to the light-emitting device 400 shown in
FIG. 4B, but differs at least in the location of the connector pads
612. The connector pads 612 shown in FIG. 6 are not located at the
side of the light-emitting device 600, but are located at a
distance from each side of the light-emitting device 600. During
some sawing processes, any metal portions, such as the connector
pads 612 may be ripped off of the device during the sawing process
if the metal portion is within the saw line 780 (See FIG. 7H).
Thus, the separation of the metal connector pads from the sides of
the device ensures the formation of the connector pads 612 without
being ripped off during any sawing processes of manufacturing.
[0031] FIGS. 7A-7H illustrate how the light-emitting devices 700
are fabricated using a group casting method as discussed with
reference to the flow chart of FIG. 8. Referring to FIGS. 7A-7H and
FIG. 8, the method for fabricating light-emitting device 700 (shown
in FIG. 7h) starts with step 810 in which a plurality of light
source dies 730 are attached on a substrate 710, as shown in FIG.
7A. In the embodiment shown in FIG. 7A, the substrate 710 is a PCB
having four groups of light source dies 730 (See also FIG. 7B),
attached to a top surface of the substrate 710. Each group may
comprise 150 light source dies 730. Alternative numbers and
arrangements may be possible, depending on design and manufacturing
requirements. For non-flip chip type of light source dies 730,
optional step 810a may occur, in which wire bonding the light
source dies 730 to the substrate 710 may be required. Next, the
method proceeds to step 820 in which a casting member 760, having
at least one cavity is aligned to the substrate 710, such that the
light source dies 730 are enclosed within the cavity. In the
embodiment shown in FIG. 7A, the casting member 760 is a casting
rubber member defining four cavities configured to enclose each
group of the light source dies 730. Other arrangements may be
possible, including a casting member of other materials. In step
830, the casting member 760 and the substrate 710 are clamped
together, using a casting jig 770a-770b, to fix the position of the
casting member 760 relative to the substrate 710 as shown in FIG.
7B.
[0032] In step 840, which may be done concurrently to steps
810-830, an encapsulant having wavelength-converting material
therein may be premixed. Step 840 can also be done before or after
steps 810-830. The encapsulant is in A-stage that is a liquid form.
The premixed encapsulant may be placed in a dispensing apparatus
780, as shown in FIG. 7C. Generally, the encapsulant needs to be
used within a predetermined time period after preparation.
Therefore, although the premixing of encapsulant may be done
concurrently or prior to steps 810 to 830, usually step 840 is
carried out after the die attach and wire bonding are done. The
encapsulant may be silicon, epoxy or any other similar
material.
[0033] The method then proceeds to step 850, in which the premixed
encapsulant is dispensed into or over the cavities. In the
embodiment shown in FIG. 7D, the dispensing is done in a zip-zag
manner. However, other dispensing patterns may be used. Next, in
step 860, the wavelength-converting material is then allowed to
sink or settle, such that a low density layer and a high density
layer are formed. In the low density layer, the
wavelength-converting material (shown in FIG. 4C) suspends within
the encapsulant 740 in particle form. On the contrary, the high
density layer comprises of a layer of precipitated
wavelength-converting material. In the embodiment shown in FIGS.
7A-7H, the sinking or settling process is done having the top
surface of the substrate 710 facing upwards. Therefore, the high
density layer is formed in direct contact with the top surface of
the substrate. If the sinking process is done in an opposite manner
in which the top surface of the substrate 710 faces downwards, the
low density layer will form in direct contact with the top surface
of the substrate 710. The sinking process may be done under a
condition such as the casting jig 770a-770b is rotated to ensure
that the thickness of the encapsulation layer is substantially
consistent. Next, the method proceeds to step 870 in which the
encapsulant is cured into a solid form. Step 860 and step 870 may
be done substantially simultaneously. Step 860 may also comprise
other details, such as degasing the encapsulation layer. In yet
another embodiment, the step 870 of curing the encapsulation layer
may be done in a temperature under 150 degrees Celsius for 4 hours,
which is done after step 860.
[0034] Next, the process proceeds to step 880, in which the casting
member 760 and the casing jig 770a-770b are removed, as shown in
FIGS. 7F-7G. Finally, the method proceeds to step 890, in which
each individual light-emitting is isolated, for example by means of
sawing. In the embodiment shown in FIG. 7H, the common substrate
710, having a plurality of light source dies 730 being encapsulated
within a layer of encapsulation layer may be sawed. This step may
also be accomplished by means of chemical or laser etching, or
other known separation means. Generally, the meniscus or curvature
portions are formed at the outer perimeter of the encapsulation
layer, because this is where the liquid encapsulant touches the
casting member 760. An area at the outer perimeter of the
encapsulation layer may be selected to define a dummy area 745.
Dummy area 745 is an area where the substrate 710 is without
attached light source dies 730 or circuits but being enclosed by
the encapsulation layer. The size of the dummy area 745 is selected
such that meniscus or curvature portions are formed only within the
dummy area 745. The dummy area 745 can be easily removed by sawing
or other separation means. Compared to the light-emitting device
200 shown in FIG. 2 manufactured using a transfer mold method, the
elimination of the dummy area 745 is cost effective. Casting the
light-emitting devices 700 in groups reduce the dummy area 745
needed per unit of devices.
[0035] FIG. 7H shows saw or separation lines 780 dividing the
substrate 710 into columns and rows to yield a rectangular shape
light-emitting device 700. As the side of the light-emitting device
is produced through sawing, the size and shape of the encapsulation
layer and the substrate 710 are substantially similar. One cost
effective shape for the light-emitting device 700 is rectangular
shape as more devices can be fit per unit area. However, for any
other customization or any needs to adapt the form factor into
other shapes, the method illustrated in FIG. 8 is applicable. For
example, for a disc shape device, the isolation of individual
devices may be done through laser cutting, V-cutting, stamping or
any other similar process instead of the sawing process illustrated
in the example given above.
[0036] Although specific embodiments of the invention have been
described and illustrated herein above, the invention should not be
limited to any specific forms or arrangements of parts so described
and illustrated. For example, the light source die described above
may be an LED die or some other future light source die. Likewise,
although a light-emitting device with a single die was discussed,
the light-emitting device may contain any number of dies, as known
or later developed without departing from the spirit of the
invention. The scope of the invention is to be defined by the
claims appended hereto and their equivalents. Similarly,
manufacturing embodiments and the steps thereof may be altered,
combined, reordered, or other such modification as is known in the
art to produce the results illustrated.
* * * * *